Many electronic devices communicate with each other using wireless local area networks (WLANs), such as those based on a communication protocol that is compatible with an Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard (which is sometimes referred to as ‘Wi-Fi’). In Wi-Fi, different electronic devices that are associated with an access point (which are sometimes referred to as ‘stations’) contend for a shared channel or communication medium. When transmissions from another station are detected, a station may ‘back off’ or wait until the shared channel is deemed free before attempting to transmit a frame. In particular, when a received energy exceeds a clear channel assessment (CCA) threshold, the shared channel may be considered busy.
This distributed approach for accessing the shared channel can result in collisions between the transmissions from different stations, which may result in retries and, more generally, reduced communication performance. These challenges can be significant in very crowded environments, where multiple stations are contending for the shared channel. Consequently, in crowded environments, delays in accessing the shared channel may increase the latency and may reduce the data rate.
Recently, in the IEEE 802.11ax standard, it has been proposed that individual stations be allowed to adapt their transmit power control (TPC) and their overlapping basic service set (OBSS) CCA thresholds. In particular, it has been proposed that a station may raise its OBBS CCA threshold while reducing its transmit power. In principle, this capability may allow the station to be more aggressive in accessing the shared channel in the presence of received energy associated with transmissions from one or more other stations, while reducing its transmit power so that it reduces its interference with respect to the one or more other stations. Therefore, the proposed adaption may provide improved communication performance for stations, especially when operating in crowded environments.
In practice, however, this approach may pose additional challenges. For example, when a station lowers its transmit power, it increases the likelihood that it becomes a hidden node to another station in the WLAN. Additionally, if a station reduces its transmit power when it raises its CCA threshold, this may result in a reduced ability for other stations in the WLAN to hear the transmissions from station A. Consequently, another station may simultaneously transmit within the same WLAN or basic service set (BSS). These concurrent transmissions may result in a collision at an access point that is associated with both the station and the other station.
Therefore, paradoxically, the proposal to allow individual stations to adapt their TPC and their overlapping basic service set OBSS CCA thresholds may degrade the communication performance, and, thus, may frustrate users of the electronic devices and degrade the user experience.